Magnetic signaling well tubing nipple



Aug 3, 1965 w. s. OWNBY MAGNETIC SIGNALING WELL TUBING NIPPLE Original Filed April 19. 1961 nav Llln United States Patent Original application Apr. 1?, 1961, Ser. No. 104,051.

Divided and this application Feb. 17, 1964, Ser. No. 345,316

1 Claim. (Cl. 166-65) This invention relates to well working equipment and more particularly to the signaling of work at a selected depth in a well hole.

This application is a division of copending application S.N. 104,051, filed April 19, 1961, disclosing a self contained tool which is triggered into action by electromotive force generated by tool travel through a signaling field. A signaling field is provided at one or more downhole stations within a well tubing string assembly. Each station involves a magnetic field protruding inwardly from the tubing wall for efiecting response of a tool carried field influenced component presented to the magnetic field.

An object of the invention is to provide a tubing string having a number of spaced apart signaling stations, each comprising a pair of magnetic fields differently spaced apart in each station and for co-operation with a running tool having transducers to be influenced upon traverse of a selected station for directing bias voltage to a pair of circuit controlling semiconductor rectifiers.

A further object is to provide an improved tubing string signaling marker comprising a tubing section of nonmagnetic material interiorly faced by a stack of co-0perating rings certain of which are longitudinally spaced apart permanent magnets having their opposite poles axially spaced apart and providing inwardly protruding fields to be traversed by similarly spaced apart field detectors of a subsurface tool for signaling tool actuation.

Additional objects and advantages will become apparent from the accompanying drawing, wherein FIG. 1 is a fragmentary view of a tubing string and co-operating running tool in vertical section; and

FIGS. 2 and 3 are vertical sections of fragments of the tubing sections at different signaling stations.

Referring to FIG. 1, a portion of a wire line running tool for electrically controlling an operation is illustrated and the operation to be controlled may be considered as the setting of a latch unit in any one of a number of receivers in a tubing string and in response to moving traverse of a set of spaced apart transducers through a pair of magnetic fields positioned by the tubing string adjacent the predetermined receiver and in a spaced apart relation different from the fields at other receivers and to which distinctive spaced relation the transducer spacing has been coded or matched by a preset selective combination of a particular pair of running tool carried transducers.

As herein shown, the tubing string section or nipple 1 has an upper counterbore or pocket ending at a bottom shoulder 3. The wall of the nipple is of brass or other suitable nonmagnetic material and has fitted within it an end to end succession or stack of rings seated downwardly on the shoulder 3 and preferably of the same internal diameter as the main bore of the nipple. Included in the stack are a set of two permanent magnet rings 4 and three nonmagnetic spacer rings 5 togther with a top nonmagnetic ring 6 for retentive bearing cooperation with a spring expander ring 7 for a removable snap fit into a cooperating groove in the nipple wall. Rings of the same or of different lengths can be employed but in any event the magnet rings and the spacer rings 4 and 5 respectively are interchangeable as to their successive relationship for obtaining diverse spacing between the upper and lower magnet rings, as will be appreciated by a compari- 3,198,255 Patented Aug. 3, 1965 son of FIGS. 1, 2 and 3. While the number of different magnet space relations can be varied and a greater number of spacer rings can be employed, it is to be expected that a well tubing string will ordinarily require latch receivers at no more than three locations and the variance in magnet spacing as illustrated will afford distinctive signals at three stations. In each instance, the lower magnet ring is retained at the bottom of the stack for simplifying the arrangement of magnet influenced elements of the running tool.

For co-operatively influencing the running tool transducers, as will later be more apparent, each magnet ring 4 is magnetized longitudinally and has its opposite poles at the top and bottom edges of the ring. With the north pole at the annular upper end, the field within and throughout the ring circle will protrude radially inwardly of the tubing string and the lines of force will run in a general longitudinal direction from the upper north pole to the bottom south pole. When any such field is traversed by a transducer, an output electromotive force will be induced but only when the spacing of a pair of transducers is coded or matched with the spacing of a particular pair of fields will both transducers be influenced simultaneously for signaling the performance of a desired operation.

For response selectively to any one and not others of the several tubing string stations, a wire line running tool as disclosed in the aforementioned patent application, is employed. Such tool has operating components to be selectively actuated when a circuit is completed through a pair of semiconductor rectifiers supplied with bias voltage upon concurrent passage by a selected pair from a group of transducers, through magnetic fields of a given signaling station. Thus the body of the tool includes a coupler nipple 80, an intermediae nonmagnetic housing tube 8d, a coupler nipple 8e and a bottom section 8 Housed within the bottom section is a cartridge shell 16 containing a combustible charge 15 which when fired furnishes expanding gas pressure to act on and depress a slide plunger 17 for a latch setting operation. The charge 15 is ignited by an electrically actuated detonator in a control circuit having one side grounded through the body and the other side joined to a connector plug 18 and a socket connector 19. The circuit is completed through a pair of semiconductor rectifiers, one of which receives bias voltage generated at the coil 29 and the other of which receives bias voltage generated at the coils 2%, 29y and 292 and delivered from any such coil through a selector switch. Conductor wires joining the electrical components are grouped as a bundle 23.

The several coils are motional electromotive force detectors and are housed within the nonmagnetic body section 8d in longitudinally spaced apart succession so predetermined that any two detectors can be aligned radially with the circular magnets in the optional space settings illustrated in FIGS. 1, 2 and 3. Each detector comprises a spool 28 of high magnetic permeable material wound with many turns of insulated conducting wire. The several spools 28, held apart by tubular spacers 30, are sleeved on a hollow spindle or stud 31. A Washer and a retainer nut 32 secure the spools against the stud head 33, which in turn is threaded into the coupler 8c. The coil 29 can be paired with any one of the coils 29x, 29y and 29z through selector switch adjustment. The spaced apart relations of the coils in the three pairings will correspond to the spacing of the magnet rings shown in FIGS. 1, 2 and 3 respectively. By preselection of any pair of coils, a coded or matched relationship with the field spacing at any particular signaling station is obtained.

As each coil of a selected pair passes through any field during tool descent, an electromotive force will be directed to the semiconductor coupled to that particular coil. Such bias voltage conditions the semiconductor for the passage of battery current but unless both semi conductors are conditioned to pass current at the same time, the battery or firing circuit remains closed. Simultaneous travel of both coils of a selected pair through the pair of fields at'a tubing station to which the coils have been coded, delivers bias voltage to both series connected semiconductors for a switch-on of current for detonating or releasing the Work performing energy provided by the squib assembly.

Modifications in the structure as specifically described can be made without departing from the invention as set out in the appended claim.

What is claimed is: g

For providing a signal marker in a tubing, a tubing element of nonmagnetic material and a stack of rings fitted in interchangeable succession within the tubing element, certain of said rings being magnetized in the axial direction thereof and each of like polarity throughout its cir cular extent with opposite poles at opposite ends thereof and others of the rings being of nonmagnetic material and of lengths differing axially one from another, said others of the rings in interchangeable relation being interposed between the magnetized rings for locating the latter selectively in longitudinally spaced apart relationships.

References Cited by the Examiner UNITED STATES FATE TS 2,350,832 6/44 Segesman l6666 X r 2,830,663 4/58 Kirby 16665 2,895,092 7/59 Cluwen 317159 X 2,906,929 9/59 Wyckoff 317201 2,953,970 9/60 Maynard 317-159 X 2,983,840 5/61 Vanlperen 317-201 X 3,105,547 10/63 Ownby 166--65 3,105,548 10/63 Ownby 16665 3,105,551 10/63 Ehlert 16665 3,106,960 10/63 Doak' 166+66 CHARLES E. OCONNELL, Primary Examiner. 

